Azo dye.



UNITED "STATES. PATENT OFFICE. Y

GERMANY, ASSIGNORS TO FARBENFABRIKEN VORM. FRIEDR. BAYER. & 00., OF ELBERFELD, GERMANY, A CORPORATION OF GERMANY.

AZO DYE.

Specificationof Letters Patent.

Patented me 8, 1909.

Application filed riiiuar a, 1909. Serial No. 475,815.

To all whom it may concern:

Be it known that we, JOHANNES. Jensen and VVILHELM NEELMEIER, doctors of philosophy, chemists, citizens of the German Empire, residingat Leverkusen, near Cologne, Germany, have invented new and useful Improvements in Azo Dyes,' of which the following is a specification.

Our invention relates to the manufacture and production of new coloring matters capable of dyeing on a mordant.v

The new dyestuffs are obtained by combining the diazo compounds of such orthoaminophenol. derivatives which contain either nitro groups or halogens or both nitro roups and halogens but no sulfonic or carboxylic groups with 'beta-beta-aminonaphthols and their derivatives alkylated or arylated in the amino group.

T he new products possess the valuable property that they can be dyed on wool together with 'bichroniate in the same loath.

, They can also be dyed ona chrome mordant or according to the afte'r-chroming method.

The dyeing in one bath is best done by adding the dye with the bichroinate to the bath, entering the wool, boiling, adding acetic acid in small portions and boiling again. Black shades are obtained.

The new dyestuffs are dark powders soluble in water generally with a violet color, and soluble in concentrated sulfuric acid generally with a red color. They yield upon reduction with stannous chlorid and hydrochloric acid amino henolderivatives and alpha-beta-diamino' eta-oxy-naphthaienes- In carrying out our new process practically we can proceed as follows, the parts being by weight:

. Example :16.8 parts of 6-methyl-4-nitro- Q-aminophenol are diazotized in the usual manner by means of hydrochloric acid and 7 parts of sodium nitrite. The diazo compound is then added to an aqueous solution,

which has to be stirred, mntil the combination is finished, of '159 parts of 2.7-aminonaphthol containing an excess of sodium carbonate. The dyestuff precipitates by acid-' 'ulation. It is filtered ofi', pressed and dined.

It is a dark powder which is soluble in water with a. reddish-violet color and which is soluble in concentrated sulfuric acid with a red color. By reduction with stannous chlorid and hydrochloric acid (i-methyl-QA- diaminophenol and 2.8-diamino-7-naphthol are obtained. It dyes wool according to the above described method blue-black shades of good fastness to fulling and to light.

The process is carried out in an analogous 'manner on starting from other beta-betaaminonaphthols or their alkylated and arylated' derivatives 6. g. 2-phenylamino-7- naphthol, 2-methylamino-7-naphthol etc. Other ortho-aminophenol derivatives may be used, such as 4-chloro-2-aminophenol, 4.6- dichloro-2 aminophenol, l-nitro-Q-aminophenol, 5-nitro-2aminophenol, picramic acid, 6-chloroet nitro-2eaminophenol, 6-nitro-4- chloro-Q-a'miriophenol, '4-methyl-6-nitro-2- aniinophenol, 2.4-dinitro-3-methyl-6-a1ninophenol, 5-nitro-4-chloro-2-aminopheno1 etc.

Having now described our invention and in what manner the same is to be performed,

what we claim as new and desire to secure by Letters Patent is *1. The herein-described new azo dyestufis, obtainable from ortho-a-minophenol derivatives containing nitro groups or halogens or both nitro groups and halogens but no sulfonic and carboxylic groups and beta-betaaminonaphthol and their derivatives substituted in the amino group, which dyestufls are, after b'eingdried and pulverized, dark powders soluble in water generally with a furic acid with a red color, yielding upon our hands in the presence of two subscribing reduction with stannous chlorid and hydrowitnesses, chloric acid 6-methy1-2.4rdiaminophenol and 2.8-diamin0-7 -naphth01; and dyeing wool together with bichromate and acid in the same bath blue-black shades fast to fulling and Witnesses: to light, substantially as described. OTTO KGNIG,

In testimony whereof we have hereunto set WM. WASHINGTON BRUNSWICK.

JOHANNES JANSEN. [1,. 8.] WILHELM NEELMEIER. [LJSJ 

